Your search resulted in 38 documents. Displaying 25 entries per page.
Biological control with Trichoderma harzianum in relation to the formation for spores the production of soluble metabolites
1994 - IRG/WP 94-10073
The amount of spores produced by three strains of Trichoderma harzianum on the aerial mycelium of agar cultures and in shake cultures, respectively, correlated with the inhibition zones exerted against Phanerochaete chrysosporium in an agar diffusion test. The amount of soluble antifungal metabolites as well as the protein content also correlated with the inhibition zones and the amount of spores produced. The antifungal metabolites were identified to be trichorzianines. They were the only compounds with antifungal activity. It is concluded that the trichorzianines are responsible for the biocontrol effect by soluble metabolites and that they are produced during conidiogenesis.
J Bürgel, E Horvath, J Haschka, K Messner
Antifungal mechanism of dichloro-N-octylisothiazolone
1998 - IRG/WP 98-30183
4,5-dichloro-N-octylisothiazolin-3-one (DCOI) is a member of the isothiazolone class of preservatives, whose antimicrobial mechanism of action has been intensively studied over the last decade. DCOI has also been intensively studied for use in wood preservation. The isothiazolones are electrophilic molecules that rapidly react with thiol groups to form covalently bonded isothiazolone-thiol adducts. This ability to bond with thiol groups is crucial to their ability to act as preservatives. Thiol groups are present in proteins as part of the amino acid cysteine, where they play an important role in maintaining protein structure and function. A number of enzymes have thiol groups at the site where the enzyme function is performed, and these thiol groups may participate in the enzyme reaction. If the isothiazolone reacts with this thiol group, the activity of the enzyme is inhibited. Our studies have shown that there are several enzymes in the Krebs cycle that are inhibited by isothiazolones and these enzymes are required to generate energy and perform many biosynthetic functions. Reflective of this, DCOI has been shown to be a rapid inhibitor of cellular respiration, causing the cell to cease consuming oxygen almost immediately upon contact with DCOI. The multiplicity of targets and their central importance to the metabolism of the cell, as well as the fact that all microbes use at least parts of the Krebs cycle, can be related to the low use levels and broad spectrum of activity of DCOI. The antimicrobial mechanism of DCOI results in a potent rapid-acting preservative with a broad spectrum of antifungal and antibacterial activity that is effective at low levels.
J S Chapman, M A Diehl, K B Fearnside, L E Leightley
Antifungal activity of a stilbene glucoside from the bark of Picea glehnii
2001 - IRG/WP 01-10402
Stilbene glucosides are widely distributed as phenolic extractives in the bark of Picea glehnii, a commercially species planted in the northern area of Japan, and its content reaches to more than 10% by the dried weight of the bark. Although antifungal activities of these compounds have been reported, the mechanism of growth inhibition is still unclear. Isorhapontin (5,4'-dihydroxy-3'-methoxystilbene-3-ß-D-glucoside) is the major constituent of the stilbene glucosides in the bark of P. glehnii. In the present work, the relation between metabolism and antifungal activities of isorhapontin for the white-rot fungus Phanerochaete chrysosporium and the wood staining fungus Trichoderma viride was investigated. Inhibition of fungal growth was obviously depending on the conversion of isorhapontin to the aglycone isorhapontigenin (3'-methoxy-3,5,4'-trihydroxystilbene) by ß-glucosidic activities in the cultures. Exogenous addition of ß-glucosidase also enhances the antifungal activity of isorhapontin. Moreover, less than 100 ppm addition of the stilbene aglycone isorhapontigenin is sufficient to inhibit the growth of both fungi. However, further metabolism of isorhapontigenin was observed after prolonged incubation of the fungi and resulted in detoxification.
S Shibutani, M Samejima
Antifungal properties of new quaternary ammonium and imidazolium salts against wood decay, staining and mould fungi
2004 - IRG/WP 04-30347
The biological activity of twenty-four potential wood preservatives – imidazolium and quaternary ammonium salts with a modified anion structure was determined employing screening agar-plate and agar-block methods. Experiments were carried out on Scots pine (Pinus sylvestris L.) wood. The aim of the performed studies was to investigate the effect of structure modification of IC and QAC with organic anions or copper (ll) and zinc complexes on their biological activity against wood decay, staining and mould fungi. The fungicidal value of new compounds for Coniophora puteana ranged from 0.64 kg/m3 to 2.2 kg/m3. Aspergillus niger turned out to be the most resistant fungus to the action of modified IC and QACs, whereas Sclerophoma pityophila was effectively inhibited by the examined salts. The performed soil-block tests showed that the IC and QAC were leached from the experimental wood in conditions of contact with moist soil and revealed their fungal detoxification by mould fungi, especially by Gliocladium roseum. Observations made using the scanning electron microscope of the colonization and decay of treated wood by mould fungi confirmed tolerance of mould fungi to QACs.
J Zabielska-Matejuk, W Wieczorek
The antifungal efficacy of Guayule resin
1987 - IRG/WP 3429
The Naval Research Laboratory is evaluating the non-rubber-producing portion of guayule (Parthenium argentatum) resin as a protectant for wood in terrestrial and marine service. This study phase, in collaboration with the universities of Arizona and Mississippi State, evaluates the resin's fungicidal worth. Resin-impregnated pine sapwood was exposed to brown rot fungi (Gloeophyllum trabeum, Antrodia carbonica, Formitopsis cajanderi, Lentinus ponderosa), white rot fungi (Dichomitus squalens, Trametes versicolor, Ganoderma sp.), and a natural inoculum of soft rot fungi from unsterile soil. The exposures for the brown and white rot fungi lasted 20 weeks, using malt agar chambers inoculated 2 weeks prior to the introduction of the treated wood; the soft rot exposure lasted 12 weeks and included treated birch specimens. Weight loss data showed a definite inhibition of decay of the treated wood by the brown and white rot fungi, however there was some decay caused by Lentinus ponderosa (closely related to creosote-tolerant Lentinus lepideus) and by Antrodia carbonica, a common utility pole fungus. None of the resin-impregnated pine or birch specimens were attacked by the soft rot fungi, even those specimens containing the lowest of the three resin concentrations in the wood. In both sets of exposures all of the controls were decayed.
J D Bultman, R L Gilbertson, T L Amburgey, J E Adaskaveg, S V Parikh, C A Bailey
Antifungal properties of metabolites produced by Trichoderma isolates from sawdust media of edible fungi against wood decay fungi
1994 - IRG/WP 94-10051
Trichoderma isolated from a sawdust medium of Pholiota nameko produced filtrates which had antifungal activities to four wood decay fungi tested on the agar plates. Filtrates produced from another isolate, from a sawdust medium of Lentinus edodes, had antifungal activities only to the white rot fungi, Coriolus versicolor and Pycnoporus coccineus. These results did not agree with those from earlier decay tests using wood blocks pretreated with the isolates. The difference of antagonistic potential was possibly due to the different condition of incubation procedure.
S Doi, M Mori
Antifungal activity in metabolites from Streptomyces rimosus
1991 - IRG/WP 1495
The objective of this study was to evaluate the efficacy of antifungal metabolites from Streptomyces rimosus for controlling the growth of sapwood-inhabiting fungi: sapstain fungi - Ceratocystis coerulescens, Ceratocystis minor, Ceratocystis pilifera, and Aureobasidum pullulans; mold fungi - Aspergillus niger, Penicillium spp, and Trichoderma spp. Production of antifungal metabolites by Streptomyces rimosus was studied using petri plate assay, plate bio-assay, wood-block tests, and green pine log sections. The metabolites inhibited mycelial growth at a distance in petri plate assay; clear zones were exhibited around the wells in plate bio-assay. Treatment of Southern Pine and sweetgum blocks and green pine log sections with concentrated metabolites inhibited conidial germination and prevented discoloration.
S C Croan, T L Highley
In vitro antifungal activity of chilli against wood degrading fungi
2006 - IRG/WP 06-10572
The efficacy of chilli juice and/or chilli extract oleoresin as antisapstain agents was evaluated against two common sapstain fungi, Sphaeropsis sapinea and Leptographium procerum. Possible synergy between chilli juice and Lactobacillus casei as antisapstain agents was also assessed. Both the chilli juice and the oleoresin showed moderate antifungal activity. No growth of the test fungi was observed on plates amended with 50% chilli juice after 3 weeks of incubation. In the presence of 0.1% oleoresins, fungal biomass was reduced by more than half when compared with unamended controls. The synergy between chilli and Lactobacillus casei was apparent; the combination of chilli/L. casei treatment system afforded much better inhibition than chilli or L. casei alone. In the presence of 25% chilli juice with L. casei the growth of test fungi was stopped.
T Singh, C Chittenden, D Vesentini
Antifungal activity of plant derived extracts against G. trabeum
2007 - IRG/WP 07-30433
While synthetic chemicals have provided excellent protection to woods used in adverse environments, the general public remains interested in naturally derived wood protectants. There are diverse arrays of possible candidates, but many of these compounds are not readily water soluble and efforts to render them soluble often reduce biological activity. In this report, we describe efforts to enhance water solubility of various plant extracts, while retaining activity against Gloeophyllum trabeum, a common wood decay fungus. The results suggest that polyvinylpyrrolidones have potential as co-solvents for many plant extracts.
M Maoz, I Weitz, M Blumenfeld, C Freitag, J J Morrell
Detection of Anti-Fungal Sapwood Extractives in Non-Durable Scots Pine (Pinus sylvestris), Rubberwood (Hevea brasiliensis) and Jelutong (Dyera costulata)
2007 - IRG/WP 07-10634
A general laboratory bioassay method of Woodward and Pearce (1985) was adopted to detect anti-fungal activity of sapwood or heartwood extractives of 5 Malaysian hardwoods [dark red meranti heartwood (Shorea spp.), red balau heartwood (Shorea spp.), kulim heartwood (Scorodocarpus borneensis), jelutong sapwood (Dyera costulata) and rubberwood sapwood (Hevea brasiliensis), including the temperate Pinus sylvestris (Scots pine sapwood). The heartwoods of these species and Scots pine sapwood are known to be highly resistant to decay by soft-rotting Ascomycetes and anamorphic fungi (about 1-7% wood mass loss), while the sapwoods of rubberwood and jelutong had much reduced soft rot resistance (respectively 35, 32% wood mass loss) but obviously prone to sapstain and mold attack, including that of Scots pine. Crude methanol extracts of woodmeal samples of each wood species were loaded on to thin-layer chromatography plates at between 0.003 and 0.1 g fresh mass equivalent of woodmeal per spot so as to optimize resolution of separated compounds, and developed with chloroform:methanol solvent (ratio 19:1). The dried plates were sprayed with fresh fungal spores of Cladosporium cucumerinum and incubated at >90% RH for 5 days in the dark. Presence of anti-fungal compounds was revealed by white regions along the solvent transect for each extract of each species where inhibited spore germination and mycelial growth of C. cucumerinum occurred. Comparisons of anti-fungal activity of extracts between species and between sapwood and heartwood were made. Results revealed that several zones of inhibitory activity, indicated by their Rf-values, were clearly visible on chromatographic separations of methanol extracts of these 5 wood species. The inhibitory zones for 2 heartwood extracts (except kulim) did not move from the origin which was also resistant to infection. However inhibition zones were also detected for the sapwoods of rubberwood, jelutong and Scots pine against C. cucumerinum despite the known sapstain and decay susceptibility of these wood substrates. The presence of hitherto unidentified anti-fungal compounds in the sapwoods of these species may elicit limited potency or narrow spectrum protection from fungal infection and onset of stain or decay.
A H H Wong, R B Pearce
Antifungal activity and synergistic effect of cinnamaldehyde combined with antioxidants against wood decay fungi
2007 - IRG/WP 07-30445
The objective of this study was to investigate the antifungal activity and synergistic effect of cinnamaldehyde combined with antioxidants against wood decay fungi. Five antioxidants, propyl gallate, octyl gallate, quercetin, eugenol and catechin were tested against various wood decay fungi. Octyl gallate and eugenol were found to be the only two antioxidants processed antifungal activities. IC50 values of octyl gallate were 0.47 and 0.04 mM against L. betulina and L. sulphureus, respectively. The IC50 values of eugenol were 0.37 and 0.25 mM against L. betulina and L. sulphureus, respectively. The synergistic effects were also found on the combinations of octyl gallate-cinnamaldehyde and eugenol-cinnamaldehyde. The combination of either using octyl gallate with cinnamaldehyde or eugenol with cinnamaldehyde greatly reduced the concentrations to achieve the inhibitory effect that a higher concentration was needed by octyl gallate, eugenol or cinnamaldehyde alone. The antifungal action of octyl gallate could be attributed to its pyrogallol group functioning as an attached moiety to the hydrophilic portion of the membrane surface and the octyl moiety interfering with the hydrophobic interior surfaces of the membrane. Meanwhile, the synergism of cinnamaldehyde with octyl gallate or eugenol could be due to the interference of fungal cell wall synthesis and destruction on cell wall and membrane plus the additional radical scavenging effect. Results also suggested that antioxidant with fungicidal effect might be a better candidate than pure antioxidant for the system of fungicide/antioxidant.
Fu-Lan Hsu, Tsair-Bor Yen, Hui- Ting Chang, Shang-Tzen Chang
Effect of cinnamon oil and clove oil against major fungi identified from surface of rubberwood (Hevea brasiliensis)
2007 - IRG/WP 07-30446
Antifungal activities of cinnamon oil and clove oil at ratio 1:1 and pure against major fungi found on surface of rubberwood (Aspergillus niger, Penicillium chrysogenum, and Penicillium sp.) were investigated using the broth dilution method. The minimum inhibitory concentration (MIC) of the combined cinnamon and clove oils for these test moulds was determined to be 80 µL/mL which were less than or equal to the MIC of the pure oils. Antifungal activity of the combined cinnamon and clove oils at the MIC was further examined on rubberwood. It was found that all moulds on rubberwood were completely inhibited for at least 12 weeks under the storage condition at 30°C and 100%RH.
Narumol Matan, Nirundorn Matan
Antifungal activity of different molecular weights of a biopolymer chitosan against wood decay fungi
2008 - IRG/WP 08-30456
In recent years chitosan has been investigated as a natural polymer for wood preservation against fungal decay. From an environmental point of view, chitosan seems to possess a potential approaches as wood protecting agent. In this study, three different molecular weights of chitosan compounds (with approximately the same degree of deacetylation 83 ± 2 %) were evaluated as in vitro and in vivo assessments against two wood decay fungi (Coriolus versicolor and Poria placenta). Average molecular weights of chitosan samples were determined by measurements of intrinsic viscosity and were found to be 3.60×105 Dalton for low molecular weight (LMW), 6.11×105 Dalton for medium molecular weight (MMW) and 9.53×105 Dalton for high molecular weight (HMW). In vitro antifungal assay was carried out using of a mycelial radial growth inhibition technique. The results showed that the antifungal activity was increased with a decreasing of the molecular weight and a LMW chitosan was exhibited a high antifungal potency against Coriolus versicolor and Poria placenta with EC50 of 1876 and 1744 mg.L-1, respectively. In addition, the results revealed that Poria placenta was more sensitive to these compounds than Coriolus versicolor. Preliminary in vivo biological test was carried out on malt agar using a miniblock technique for beech and Scots pine sapwood with Coriolus versicolor and Poria placenta, respectively. After six weeks of exposure to fungal attack all chitosan protective systems tested proved their relative effectiveness when compared to the control specimens. Furthermore, chitosan LMW was the most effective compound among all treatments at the higher concentration against the tested fungi.
A S O Mohareb, M E I Badawy
Investigation into the antifungal properties of herbal remedies for potential use in the wood preservation industry
2008 - IRG/WP 08-30462
The efficacy of herbal remedies as potential antifungal agents was evaluated against two sapstain and three decay fungi. Sapstain fungi included Sphaeropsis sapinea, and Leptographium procerum, and decay fungi were Oligoporus placenta, Coniophora puteana, and Schizophyllum commune. Out of six herbal remedies tested, three showed moderate to high antifungal activity. Caprylic acid had high antifungal activity (MIC of 0.005 – 0.025% w/v dependant on fungi) when tested on Petri-dishes and moderate activity when progressed to pure culture wood decay trials. Pau d’arco and echinacea both showed moderate antifungal activity in vitro. There appeared to be an enhanced antifungal activity when caprylic acid with pau d’arco or caprylic acid with echinacea was evaluated. However when all three extracts were tested in combination, activity decreased.
Antifungal activity of essential oils against common wood degrading/decaying fungi
2008 - IRG/WP 08-30465
Despite the wide use of essential oils in pharmaceutical and food industry as antimicrobial agents, their use as wood preservatives has not been fully explored. In this study, 12 essential oils were screened in nutrient medium for their antifungal activity against 8 common mould, sapstain or decay fungi. Subsequently, one essential oil, eugenol was evaluated for decay resistance in an agar/wood block tests using both unleached and leached cycles with radiata pine sapwood blocks. During the initial in-vitro screening trial, variability in the tolerance of the tested fungi towards the selected essential oil was apparent. Some of the essential oils such as geranium, cinnamon leaf and eugenol completely inhibited the growth of all test fungi at 0.5% w/v on nutrient medium, whereas, three essential oils; eucalyptus, olive leaf and kolorex® were unable to restrict the growth of any test fungi even at 1% w/v concentration. Durability test results on radiata pine confirmed the antifungal activity of eugenol but highlighted the leachibility of this compound from wood. Blocks treated with 3% w/v eugenol without a leaching cycle had less than 1% weight loss when exposed to all three tested wood decaying fungi, Oligoporus placenta, Coniophora puteana and Antrodia Xantha. However, blocks which were leached showed weight losses in the range of 13.40 to 23.12%. This study identified eugenol as a potential benign wood preservative for treatment of timber not exposed to severe leaching, e.g. New Zealand Hazard Class H1.2. However, to be used for higher decay hazard situations, further work for in-situ polymerization of eugenol to fix active(s) in wood will be required.
T Singh, C Chittenden
The Comparison of Fixation and Leachability of Bark, Fruit and Leaf Tannin Extracts with Boron Minerals
2008 - IRG/WP 08-30473
Tannins extracted from several plants have natural durability properties. Due to these properties, some of the researchers have studied them for protecting wood. In this study, Scots pine (Pinus sylvestris) and beech (Fagus orientalis) wood samples were treated with bark, fruit, and leaf extracts as well as water-based wood preservative salts at various concentrations to increase fixation. The penetration, fixation, and antifungal properties of different treatment solutions were compared. Retention levels were generally higher for Scots pine wood than beech wood. The highest retention levels were seen in wood treated with valex and sumex, which are extracts of oak fruits and sumac leaves, respectively. Leaching tests indicated that both wood types treated with sumac extracts showed higher retention levels than wood treated with the other fruit and bark extract solutions. Adding 1% water-based wood preservative salts to valex and sumac extracts increased the retention levels. Higher concentrations of wood-preserving salts accelerated and increased the amount of leaching. We found that the extract alone was resistant to leaching. Mycological tests showed that bark extract solution was the most effective at preventing mycelium penetration and that adding water-based wood-preservative salts to all extract solutions significantly affected the resistance of the wood against fungal infection.
S Sen, C Tascioglu, K Tirak
Antinomic natural self-protection mechanism in long-lasting woods: a case study with three tropical species from French Guiana
2009 - IRG/WP 09-10696
We demonstrate in this work through 3 examples that Amazonian trees may specialize long-lasting woods by means of at least to different approaches. Wallaba impregnates its wood with large amounts of weakly antifungal compounds acting in synergy, while tatajuba and louro vermelho woods are naturally impregnated with antifungal agents. Comparison of biological activities in vitro and concentrations in the woods indicate that these compounds alone may account for the natural durability of the two woods.
A Rodrigues, M Royer, N Amusant, J Beauchêne, G Herbette, V Eparvier, A Thibaut, L Salmen Espíndola, B Thibaut, D Stien
Antifungal Activities of Three Supercritical Fluid Extracted Cedar Oils
2009 - IRG/WP 09-30501
The antifungal activities of three supercritical CO2 (SCC) extracted cedar oils, Port-Orford-cedar (POC) (Chamaecyparis lawsoniana), Alaska yellow cedar (AYC) (Chamaecyparis nootkatensis), and Eastern red cedar (ERC) (Juniperus virginiana L), were evaluated against two common wood decay fungi, brown-rot fungi (Gloeophyllum trabeum) and white-rot fungi (Trametes versicolor). The statistical analysis showed that SCC extracted cedar oils had higher antifungal activities othan hexane Soxhlet extracted cedar oils against both white-rot fungi and brown-rot fungi. In vitro studies showed that AYC oils showed the strongest antifungal activity among the three cedar wood oils, followed by POC oil and ERC oil.
Tianchuan Du, T F Shupe, Chung Y Hse
Potential of antifungal and antitermitic activity of several essential oils
2009 - IRG/WP 09-30515
In the recent years, there has been an increasing concern regarding the safety of wood preservatives. Many research groups have examined the potential of essential oils as biocide based on their biological activity. This paper described the antitermitic and antifungal activity of twenty four essential oils from different plant species. The termicidal activity was carried out with a no-choice test with impregnated filter papers at several concentrations. Screening tests with mycelium of basidiomycete with different concentrations of essential oils were used to assess the fungicidal activity. The essential oils were less active against termites than fungi. Essential oil from savory was the most active and the threshold is under 1% while six essential oils were active against white and brown rot with a threshold under 0.1% (v/v). These results suggest essential oils may be active ingredients of interest for the development of wood preservatives.
N Amusant, M-F Thévenon, N Leménager, E Wozniak
Antifungal Essential Oil Metabolites
2010 - IRG/WP 10-30531
New environmentally-friendly wood protection systems based on “green” technologies are needed to inhibit wood-inhabiting mold and decay fungi. Utilizing bioactive essential oils from select herbaceous plants is one promising approach, but the concentrations of bioactive compounds are somewhat variable even in the highest (therapeutic) grade essential oils. Purified primary metabolites from four bioactive plant essential oils were evaluated for antifungal activity in southern pine treated with those compounds. Purified carvone, citronellol, geraniol, thymol and borneol inhibited growth of Aspergillus niger, Penicillium chrysogenum and Trichoderma viride for 12 weeks at concentrations equal to or less than those present in therapeutic grade essential oils. Thymol and borneol effectively inhibited two brown-rot fungi, Postia placenta and Gloeophyllum trabeum and one white-rot fungus, Trametes versicolor, but other metabolites tested were ineffective against the decay fungi. Select purified bioactive metabolites of essential oils effectively inhibit fungi that inhabit wood and wood products.
C A Clausen, B M Woodward, V W Yang
Antifungal Effect of Bark and Wood Extracts of Condalia hookerii (Rhamnaceae), Ebenopsis ebano (Fabaceae) and Helietta parvifolia (Rutaceae) on Trametes versicolor
2010 - IRG/WP 10-30532
This research detail the growing inhibition effect on Coniophora puteana and Trametes versicolor fungi caused by hot water sawdust and bark extracts of three semi-arid land species Condalia hookerii, Ebenopsis ebano and Helietta parvifolia diluted in malt extract agar medium at 2000 ppm and 10000 ppm. After 12-14 days incubation the inhibition growing effect was measured based on the difference between extracts and the control (fungi growing in malt extract agar medium without-extract). The highest growing inhibition was obtained from the fungi Trametes versicolor on malt extract agar medium from bark water extracts of Helietta parvifolia at 10000 ppm concentration. The second highest growing inhibition was amounted to 45 ± 12 for Trametes versicolor at the same species from sawdust water extracts.
A Carrillo, J G Marmolejo, F Garza, V Bustamante, M Garza
Antifungal and wood preservative efficacy of IPBC is enhanced by α - aminoisobutyric acid
2010 - IRG/WP 10-30544
There is currently a need to reduce the biocide content of wood preservatives, without decreasing efficacy. The nonmetabolised amino acid analogue α-aminoisobutyric acid (AIB) acts as a translocated inhibitor of mycelial spread in basidiomycete wood decay fungi, although it does not kill the organism. Factorial combinations of AIB with either the azole fungicide tebuconazole, or 3-iodo-2-propynyl butyl carbamate (IPBC), were tested for inhibition of growth in wood decay fungi. The concentration of IPBC required for 95% inhibition of the three fungi tested was reduced by approximately 50% in the presence of 2g/l AIB. AIB did not enhance the inhibitory effect of tebuconazole. Using a the accelerated EN113 test for decay of treated wood blocks, AIB at 1g/l was found to reduce by the concentration of IPBC required for a wood preservative effect.
P Bota, E Baines, A Mead, S C Watkinson
Antifungal activity of wood extractives from waste products of steam distillation of Aniba rosaeodora
2012 - IRG/WP 12-10779
Aniba rosaeodora, is a slow growing evergreens of the Lauraceae family which are indigenous over a wide range of the Greater Amazon Region (the Guianas and Venezuela, Brazilian Amazon…). The essential oil obtained from the wood has a characteristic aroma and is a long-established ingredient in the more expensive perfumes. Around the olfactive characteristic of the essential oil is due to the presence of levogyre linalol. The steam distilled wood oil is obtained in a yield ranging around 1% and up to 90% of the oil consists of optically active linalol. This work is focused on the valorization of steam distillated sawdust, waste obtained from extraction of essential oil. After steam distillation, the sawdust was extracted by ethyl acetate and methanolic solvents and the antifungal activity was evaluated against basidomycetes fungi. The both extracts were active in vitro against white and brown rot fungi and allowed to propose these extractives as wood preservative agent.
N Amusant, A Digeon, E Hoüel, J Beauchène
Antifungal activities of acetone-soluble Eusideroxylon zwageri and Potoxylon melagangai crude extracts against white rot
2012 - IRG/WP 12-30591
The development of natural wood extracts as a wood preservative is a potentially attractive prospect for the wood preservation industry. This study attempts to evaluate the toxicity of Eusideroxylon zwageri and Potoxylon melagangai extractives as potential wood preservatives. These two species are well-known as among the heaviest and very durable timbers. It has been established that natural durability of timbers are associated by their extractives contain. In this study acetone was used to remove extractives from both wood samples and later was purified by using rotoevaporation process. The toxicity of various extract concentrations against two white rot fungi, Pycnoporus cocinneus and Schizophyllum commune was evaluated on MEA agar for seven days period. Results showed that the mean growth rate of fungi decreased with increased in level of concentrations. Toxicity test indicated that in 1000 ppm concentration, the extractives of E. zwageri reduced the growth rate of P. cocinneus and S .commune by 26% and by 36% while P. melagangai extractives reduced P. cocinneus and S. commune growth rate by 36% and 41%, respectively. Various extract concentrations were used to treat Hevea brasiliensis wood blocks. Following exposure to the white rot fungi for eight weeks it was observed that the weight loss reduced significantly when treated with 15% acetone-soluble extractives. This suggests that transferred extractives have the potential to control decay. However, further studies are required before any concrete inferences can be made on extractives for natural wood preservatives.
I Jusoh, A Tida Henry, Z Assim, F Badruddin Ahmad, S Ujang
Antifungal properties and bonding of menthoxymethylimidazolium ionic liquids with Scots pine wood
2013 - IRG/WP 13-30627
Antifungal activities of five chiral ionic liquids - menthoxymethylimidazolium derivates against brown-rot decay fungus (Coniophora puteana), white-rot decay fungus (Trametes versicolor) and blue-stain fungus (Sclerophoma pithyophila) were determined using screening agar-plate method. Results from antifungal tests revealed that 1-butyl-3- menthoxymethylimidazolium chloride exhibited the strongest antifungal activity against wood decay fungi (Basidomycotina) compared with the commercial DDAC. Whereas compound with nine carbons alkyl substituent had strong fungistatic effects. Sclerophoma pithyophila fungus was most resistant to the action of this natural origin ionic liquids. The infrared spectral analysis (FT-IR ATR) confirmed that chiral imidazolium ionic liquids were built into the structure of the treated wood.
J Zabielska-Matejuk, J Feder-Kubis, A Stangierska